The embodiments described herein relate generally to fluid transfer medical devices. More particularly, the embodiments described herein relate to devices and methods for placing a catheter within a vein, via an indwelling peripheral intravenous catheter, at a position suitable for blood aspiration.
The cutaneous veins of the forearm and hand are the most accessed sites for intravenous catheter insertions and venipunctures for infusing fluid into and/or aspirating bodily fluid from a patient. The standard procedure for blood extraction (i.e. phlebotomy), for example, involves percutaneous insertion of a metal needle (“butterfly needle”) into a patient to gain access to that patient's vein. The typical hospitalized patient encounters a needle every time a doctor orders a lab test. Repeated needle “sticks” are not only painful and a major source of patient dissatisfaction, but can lead to significantly higher material and labor costs (needles and tubing must be disposed of after every attempt).
While most hospitalized patients receive a peripheral intravenous (PIV) catheter that is configured to dwell within a vein for an extended period, PIVs are generally used for infusing fluids and medications rather than blood extraction. In some instances, for example, the failure rates for aspiration reach 20-50% when a PIV has been indwelling (e.g., disposed in a vein) for more than a day. Blood extracted from PIVs is often hemolyzed (i.e., the red blood cells are often ruptured and their contents released), which can result in an unusable sample and a need to repeat the blood collection.
Several barriers can contribute to the shortcomings of extracting blood through a PIV. Such barriers can include, for example, catheter malfunctions, occlusion of the vein resulting from the indwelling of the PIV, debris forming around the PIV, collapse of the PIV or vein in response to the negative pressure during aspiration, and/or the like. In addition, the venous anatomy of the forearm and hand have not been well studied or described and, as such, the venous anatomy itself and/or characteristics of blood flow paths therethrough can further present barriers to phlebotomy through an indwelling PIV.
Thus, a need exists for improved understanding of the venous anatomy and for devices and methods for placing a catheter within a vein, via an indwelling PIV, at a position suitable for blood aspiration.